The hepatic immune system plays important roles not only in eliminating in pathogenic microorganisms, toxins, and tumors, but also in induction of immune tolerance. The hepatic lymphocyte population is enriched in innate immune cells including macrophages (ie, Kupffer cells), natural killer T cells, and natural killer cells, which are activated during viral infection or by TLR3 ligand injection. The innate cytokine interferon-alpha is primary choice for the treatment of hepatitis B and hepatitis C infection, which affect half a billion people worldwide. This lab is interested in 1) studying the role of innate immune cells and innate cytokines in liver injury, fibrosis, regeneration, and liver tumor transformation; 2) studying liver immunology. We have demonstrated (1) that natural killer cells play important rols not only in inducing liver injury but also in inhibiting liver regeneration,(2) that IL-6 protects against T cell-mediated hepatitis via inhibition of NKT cells.